The people of the island of Ireland grew tired of being assimilated as part of the United Kingdom of Great Britain and Ireland which they most recently joined in the Act of Union of 1801. The UK looked after Ireland abominably, like a hybrid colony which it was with antagonistic religions and a nasty vicious history of British military interference, and permitted famines to occur (Potato Famine) leading to mass emigration. Partition of the 6 counties of the North occurred following the unrest and civil wars which got stirred up after the end of World War 1, in which the 1916 Easter Rising rebellion was ruthlessly repressed as treasonous. The Protestants in the North of Ireland did not want to be part of the overwhelmingly Catholic South and so an artificial statelet comprising the 6 counties was put together in which there could be a natural majority in favour of remaining within the UK. So partition, it could be argued, was instituted to prevent a continuation of the Irish civil war with the need for a war-weary Britain to maintain a full military occupation. It was a very messy compromise which has produced periodic insurgencies ever since.
· 11 months ago